Dental hygiene therapy–led brief tobacco cessation and periodontal pocket reduction in Kenyan prison dental clinics: a difference-in-differences analysis of integrated care pathways

Tobacco use among incarcerated populations in Kenya is high, yet prison dental services rarely deliver structured cessation support, and the periodontal consequences of brief, dental-hygiene-therapy-led interventions in this setting remain unquantified. Using a real DHS Program indicator on injection receipt by a health care provider as a calibration benchmark for provider-mediated care coverage across 14 African countries (2021–2025; N = 14; mean 91.964; SD 12.468), the analysis specifies the identification assumptions, the parallel-trends condition and the estimator that would recover the pathway's effect on periodontal pocket depth. The design distinguishes the cessation component from the mechanical debridement component, and it treats prison-specific constraints—security escorts, short sentences, high turnover and limited therapist numbers—as effect modifiers rather than nuisance. The pathway's value lies less in the cessation advice itself than in the co-location of cessation with a procedure prisoners already attend, and it sets out the boundary conditions under which a difference-in-differences estimate would be credible. The contribution is a pre-specified, transportable evaluation architecture for integrated oral-health and tobacco-care pathways in custodial settings, together with an explicit account of what such a design can and cannot establish.